1. Field of the Invention
This invention relates to the field of critical point dryers for the preparation of biological and organic specimens for examination by electron microscopy, and more particularly to a semi-automatic critical point dryer.
2. Description of the Prior Art
In prior art manual critical point dryers, the operator was required manually to adjust a conventional two-way exhaust valve in order to obtain the proper flow rate for the very critical purge and bleed modes of the dryer operation. A skilled operator was required properly to make this valve adjustment in order to avoid damage to the specimen being dried.